1. Technical Field
The present invention relates to a hybrid vehicle and a control method of the hybrid vehicle.
2. Description of the Related Art
One proposed constant speed drive technique for automobile performs acceleration control to maximize the fuel economy against the throttle opening in response to the driver's on operation of a fuel economy drive mode selection switch (see, for example, Japanese Utility Model Laid-Open Gazette No. S63-85533). Another proposed constant speed drive technique for automobile sets an upper limit of engine rotation speed in response to selection of a fuel economy mode (see, for example, Japanese Patent Laid-Open Gazette No. 2003-343305). One proposed technique for the enhanced fuel efficiency on an upload drive specifies a maximum fuel efficiency vehicle speed in a range of ±10 km/h from a tentative target vehicle speed and sets the specified maximum fuel efficiency vehicle speed to the target vehicle speed (see, for example, Japanese Patent Laid-Open Gazette No. H08-295154). One proposed technique for hybrid vehicle keeps constant engine output during constant speed drive to enhance the fuel efficiency (see, for example, Japanese Patent Laid-Open Gazette No. 2000-8902).